The present invention relates to a liquid-cooled electric machine having liquid-cooled pressure plates of non-magnetic steel which press the stator lamination stack together.
Liquid-cooled pressure plates having pressure fingers for pressing the lamination stack of a liquid-cooled electric machine are known in the art (see the journal "Bulletin des Schweizerischen Elektrotechnischen Vereins", 1973, page 1707). Since eddy currents are induced by magnetic stray flux emanating axially from the rotor, which can lead to a considerable local temperature increase, especially in the facing end zones of stator lamination stacks of large electric machines, it is advantageous to use liquid-cooled pressure plates. Cooling pipes cast into the pressure plates, however, have the disadvantage that the heat transfer between the pressure plate and the cooling liquid is impeded by the cooling pipe or the contact between the cooling pipe and the pressure plates.